Sheet-metal-forming machine.



PATENTED JUNE 13, 1905.

G. HOFF.

SHEET METAL FORMING MACHINE.

APPLIOATION FILED NOV. 25, 1904.

2 SHEETS-SHEET 1.

Wflnssses Inventor PATENTED JUNE 13, 1905,

0. HOFP.

SHEET METAL FORMING MACHINE.

APPLICATION FILED NOV. 26, 1904.

2 SHEETS-SHEET 2.

Nib-Leases Ina 511F31 UNITED STATES Patented June 13, 1905.

PATENT OEEIcE.

CHARLES HOFF, OF CINCINNATI, OHIO, ASSIGNOR ONE-HALF TO CHARLES ANDREW, OF CINCINNATI, OHIO.

SHEET-METAL-FORMING MACHINE.

SPECIFICATION forming part of Letters Patent No. 792,132, dated June 13, 1905.-

Application filed November 25, 1904:. Serial No. 234,151.

To all whom, it may concern:

Be it known that I, CHARLES Horn, a citizen of the United States, residing at Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Sheet-Metal-Forming Machines; and I do declare the following to be a clear, full, and exact description thereof, attention being called to the accompanying two sheets of drawings, with the reference characters marked thereon, which form also a part of this specification.

This invention relates to machinery for shaping and forming containing vessels like a coal hod or bucket, for instance, out of sheet metal and where the bottom of such vessels is formed out of an excess of the metal contained in the sides, such excess being collapsed and reduced by crimping and folding the metal thereof until the proper shape is obtained. Vessels of this kind are illustrated in two of my patents, Nos. 279,871 and 303,011, which show coalbuckets in the familiar shape of substantially inverted truncated cones, the smaller end of which cone is closed and forms the flat bottom. The metal for this bottom is obtained from the complementary part or frustum of this truncated cone, which is collapsed and reduced by crimping and folding and finally flattened and forced inwardly, thus producing the bottom. The reduction proceeds by annular concentric zones, the metal within each being acted upon one after the other until all have been brought down to one level and into one plane which forms the bottom.

The present machine has for its object to act simultaneously upon two or more of these annular zones, so that a correspondingly larger area of metal is brought down and leveled at the time, thus reducing the time required to produce such a bucket and lessening correspondingly themanufacturing expenses.

In the following specification and particularly pointed out in the claims is found a full description of the invention, together with its operation, parts, and construction, which latter is also illustrated in the accompanying drawings, in which Figures 1, 2, and 3 show in side elevations and vertical cross-sections, also with parts broken away, complementary sets of dies, each performing part of the operation for producing a bottom in the manner outlined. The figures are arranged with reference to the successive steps of the operation as they follow each other for gradually reducing the conefrusturn, Figs. (6 and 6 relating in each case of Figs. 1 and 2 to the same set of dies, Fig. 6 of each merely indicating a later step with reference to Fig. (0. Fig. 4: shows the bottom finished by the complete reduction and flattening of the cone-frustum. Fig. 5 shows a bucket complete. Fig. 6, in side elevation, shows a suitable construction for operating the dies. Fig. 7 is a top view of the preceding figure.

When the material reaches my machine, it is in shape of a cone 10, as best shown in Figs. 1 or 5, and produced in any suitable Way from blanks shaped to suit the purpose. This cone is placed over the lower one of a coacting set of dies between which the reduction takes place. This lower die I call the anvil-die, and the same is indicated at A. It is supported in any suitable way and in a manner to keep it securely centered with reference to the cooperating upper dies. For such purpose a neck 11 is provided on its under side, which is fitted into a stock 12, supported on a suitable part of the machine-frame 13. The lower part of this die is tapered, as shown at 14, which taper is fitted to the tapering side of the cone, so as to support the same when operations are started, as shown in Fig. 1, (c). There is in addition a centeringrod 15, to hold the cone in proper position until operations are started. This rod, for reasons which will presently become apparent, is yieldingly supported either by a suitable counterweight or a spring 16, which returns and holds it to a fixed normal position. On the upper side of this anvil-die, as shown in Fig. 1, (a and 6,) both figures representing the same set of dies operated in the same machine, there are a number of annular steps of upwardly-decreasing diameter, as shown at 17, 18, and 19. The first reduction in the side of the cone starts on step 17, this being the line on which the side of the bucket terminates and is started to turn in to form the bottom. It is caused by the flattening-die B, of annular (cylindrical or elliptical) shape, it being one of two concentrically-arranged upper dies which act in conjunction with the anvil-die and are reciprocated with reference to this latter. The

start or first part of this first reduction is shown completed in Fig. 1, (6,) and is immediately followed by the action of the steppingdie C, moving within die B, which completes I the first reduction by forcing additional parts of the metal down against steps 18 and 19 of the anvil-die. Centering-rod 15 by reason of its sliding support readily yields to this reduction of the metal, whereby the point of the cone is lowered. Afterthisfirstreductioniscompleted the two upper dies recede from the anvil. A stripper 21 prevents the bucket-cone from following. This stripper is carried by the outer one of the upper dies; but by reason of the particular manner of its support it does not immediately follow the rising die, but is 'held down by springs 22 against the bucket-cone, thereby preventing the same from following. When the dies are lowered for action, this stripper by reason of its yielding support does not interfere with the operation. The further reduction of the bucket-cone takes place between similar sets of dies, each operated in asuitable machine or press and in a manner similar to the set shown in Fig. 1,

(a and b.) The dies being by preference exchangeable, the same press might be used to operate these succeeding sets to be used for finishing the bucket. For expeditious working it is preferable, however, to have independent machines or presses to operate these sets of dies to be subsequently used.

A second set of dies is shown in Fig. 2, (a and b.) The bucket-cone arrives on this set of dies in a shape as best shown in Fig. 2, ((0,) it being the shape received from and imparted by the dies shown in Fig. 1. -A centeringrod, as shown at 15 in Fig. 1, may be dispensed with in the use of these succeeding sets of dies, since the steps now present in the cone serve the same purpose. There is again an outer or flattening die B, which in its action flattens part of the bucket-bottom against the anvil-die A by folding the second step in the bucket-cone down and over the first one, as best shown in Fig. 2, (A) This action lowers also simultaneously the remaining part of the cone-frustum and brings the third step closer toward the anvil-die. This action is immediately followed by action of the inner or stepping die C, the first shoulder 23 of which acts against this third step by flattening it against the anvil-die and folding it at the same time over the second step, previously flattened by flattening-die B. Additional shoulders 24L and 25 on this die 0 above shoulder 23 form at the same time additional steps in the bucket-cone by indenting the metal against steps 26 and 27 on anvil-die A. This operation, by similar sets of dies A, B, and U, actuated by similar mechanical means, machines, or presses, the dies being, however, of succeeding decreasing diameter, may be repeated until the center of the bucket-cone is reached and the vertex of the frustum has been lowered down to the anvil-die. In the drawings any such additional intermediate steps of the operation and the requisite dies therefor have been omitted, since they are similar to the operation illustrated in Fig. 2, (a and 6.) Furthermore and for the sake of clearness the folds and laps have been shown rather large; nor has it been possible for the same reason to show them as closely compressed and flattened as they would be in reality.

The finishing operation is shown in Fig. 3, where the flattening-die B is about to flatten the last one of steps formed previously in a preceding set of dies against the last one of the steps previously flattened, all proceeding in the same manner as before described. This also lowers the remaining part of the conefrustum, the point in which part is also flattened by the lower end of the presently-acting inner die (I. This final action it is expected will cause the last remnant of the cone-frustum to disappear by pressing the same out flat, as best shown in Fig. 4, which shows the bottom completed, except that in reality the folds or crimps would be more completely and closely flattened against each other. Fig. 5 shows the bucket so completed also provided with an annular flange 28 around the bottom to form a base. This base may be attached in any suitable Way; but by preference it is clamped in between the first and second steps formed in the side of the bucket-cone to form the bottom. For such purpose this base is placed on the first step, as shown in Fig. 2, ((4,) and before the second step is folded down over it, so that after such is done the base is securely clamped between these two flattened steps, as best shown in Fig. 2, (6.) The strip per 21 used on this set of dies is arranged so as to fit and act against this base.

The upper dies B and 0, one within the other, may be reciprocated with reference to the anvil-die A by any suitable means and mechanism which gives the proper effect and desired results. A suitable machine is shown on the second sheet, Fig. 6 being a side elevation, and Fig. 7 a top View, .thereof. In it the outer one of the upper dies (die B) is guided between depending frame portions, forming guides 29 and forming part of a general machine-frame 31. The inner one C of the upper dies is guided by and within this outer die. The dies are moved by levers, the outer one by levers 32 and the inner one by a lever 33. The levers connect to the dies by suitable The other ends connect by rods 34 and links.

veais 35 to eccentrics 36 and 37, mounted on a shaft 38 and properly set thereon for the purpose of timing the action of the dies. This shaft may be suitably driven by a pulley or gearing, either one aided by a fly-wheel 41. It is obvious that the operation of these concentric upper dies may be accomplished by various other equivalent mechanical means, the arrangement of which would merely require the i work of the constructing machinist.

Having described my invention, I claim as new- 1. In means for reducing gradually the pointed end of a bucket-cone by successively crimping, folding and flattening parts thereof, the combination of an anvil-die, the upper surface of which is stepped off, a set of concentrically-arranged dies operating in conjunction therewith and means for actuating each of these latter dies independently.

2. In means for reducing by gradual steps the pointed end of a bucket-cone by successively crimping, folding and flattening parts thereof, the combination of an anvil-die, the upper surface of which is stepped off, a set of concentrically-arranged dies to operate in conjunction therewith and provided with steps complementary to the steps in the anvil-die and means for actuating these concentric dies, one independent of the other.

3. In means for reducing by gradual steps the pointed end of a bucket-cone by successively crimping, folding and flattening parts thereof, the combination of an anvil-die the upper surface of which is stepped off, a flat tening-die and a stepped forming-die, one arranged within the other and means for actuating these two latter dies one independent of the other.

4. In means for reducing by gradual steps the pointed end of a bucket-cone by successively crimping, folding and flattening parts thereof, the combination of an anvil die stepped off on its upper side and provided with a neck on its under side, a stock to receive this neck, a complementary set of concentrically-arranged dies to operate in conjunction with the dies first mentioned and means to actuate this latter die.

In testimony whereof I hereunto set my signature in the presence of two Witnesses.

CHARLES HOFF.

Witnesses (J. SPENGEL, ARTHUR KLINE. 

